Lap desk



FIG. 1 is a perspective view of a lap desk, showing my new design;

FIG. 2 is a top plan view;

FIG. 3 is a rear elevation view;

FIG. 4 is a left-side elevation view;

FIG. 5 is a right-side elevation view;

FIG. 6 is a bottom plan view; and,

FIG. 7 is a front elevation view thereof. 

The ornamental design for a lap desk, as shown and described. 